DESPITE THE advanced technology of Canon’s flash system, you’ll still need some old-school techniques to get the best from it. Photographic umbrellas and softboxes, for example, will help to spread and diffuse the light emitted from an off-camera Speedlite. It’s trickier to soften the light from a pop-up flash, but there are a few commercial options available. Alternatively, you can create your own by cutting up a translucent plastic milk carton.
If you want to prevent the light from the flash spilling everywhere and produce a more focused beam of light to pick our a detail, then a grid or a snoot attachment can help here.